Archbald Pothole State Park in Archbald, Pennsylvania, preserves a striking glacial pothole discovered in 1884 when coal miners extending a shaft broke into a hidden vertical opening packed with water and rounded stones. After nearly 1,000 tons of debris were cleared, mine manager Edward Jones recognized it as a geologic feature carved into bedrock by swirling meltwater during the Wisconsin Glacial Period. Measuring 38 feet deep and 42 by 24 feet at its widest, the pothole became an early tourist attraction before passing from private hands to historical, county, and then state ownership. The park links the region’s coal mining past with a far older Ice Age landscape.